Drill bit



July 8, 1952 w. R. WADE DRILL BIT 2 SHEETS SHEET 1 Filed July 20, 1948 Fmh% M g 0 ,4, M

July 8, 1952 w, W 2,602,641

INVENTOR.

Patented July 8,1952 I: I I Q I 1;;- iy 'invention mates to imp 2 drlllbit; 7 H t In.. operation a bending" force is exerted" upon 2 I the'hrill bit and' 'drill rod each-time a blowis 2 delivered on therod. The bottornpf a drill hole p p ndi isuneven. At e'ach blow of the hammer on or gut groove recei more corners of the bit will be one hump The blow causes a bending strain' at the connection of the bit to the drill rod. Aprincipal purpose of my invention is to provide a novel bit and anovel mean'sfto connect it to the drill rod, cooperating t r ue br'e' kse l ed,

it "laljs'oa perpeseerm n ntion toiirqyme ovelfdrill bit "with hardened inserts, with holes s6"6nst1iic'ted V i e ffili t oi the insrts andto in bi movement of thein'serts.

The natureand; advantages; of my invention, together withother and more specific objects theretirwillapp r more illlyiiro heiiollQW- description 'and the a ccomp'anying drawings teases i ii h 'niiist'rat 't preferred form thereof.

;;; Inthedrawings:' H I i p igure'l "is"'"alongitudinal"sectional view 1 1 through a drill bit embodying my invention; ifisert W 11 Figure 2 is a fragmentary view in side elevation through the drill r Causes a bending ac ion of the lower portion of the bit; at the connection between the bit and the drill Figure 3 i a bottom plan view of the bit; rod. The guide collar i6, which fits closely on Figure 4 is a side View of a so-called bull bit he od a er t s be di st ain up the utilizing a simple hardened insert; drill rod to a point above wher the rod is weak! Figure 5 is a sectional view taken on the line ened by a thread. This reduces breakag of the 5-5 of Figure 3; and drill rod.

Figure 6 is a bottom plan view of the bit shown The bottom of the drill rod transmits the drillin Figure 4. 5 ing blows to the center of the bit. There is ample Referring now to the drawings, my improved stock in the bit below the socket [4 to absorb drill bit is illustrated generally by the numeral this shock. The provision f the Socket l4 d m The 1 111 rod H d th p11; in r on.- the extension I5 on the rod aids in preventing nected by threading the rod into the bit. Tadamage to the threads l2 and I3. The additional pered threads [2 on the bit and matching tapered length of the bit also serves to steady it in the threads I3 on the rod serve to make this conhole and permits less torsional strain on the drill nection. It will be noted that the threads are rod. The guide collar also helps to keep the hole rounded at the peak to avoid sharp grooves in in line and reduces bending in broken rockor the drill rod and bit as sharp bottomed grooves seamy rock. promote breakage. The body of the drill bit is By my construction of the undercut grooves in long enough to provide a cylindrical socket M the face of the drill and the. tapering of the below the thread in which a cylindrical tip l5 of sides of the hard inserts 28, 29, 30 and 3|, I am the rod is seated. The bit 10 also has a collar able to retain the inserts without any welding or IE, which extends upwardly on the drill rod for vbrazing. Brazing is added generally to prevent a substantial distance above the threads l3. The the insert from being forced out sideways if one drill rod has a central water hole I! that is in end is broken off. The steel of the bit, because communication with a p a 18 n h i Th it is softer than the insert, is constantly peaned passage I8 extends downwardly into the bit betighter to the insert by the reaction oi. the steel low the socket 14 0f th d v e 0 p v tWO bit to striking the cuttings as the cutting edge of diverging passages 19 and 20 th p n elese to the hard insert is penetrating the rock. the cutting face of the bit. It will be noted that the bit has no center hole The cutting face of the bit body. as illus ra for water, instead it has the two side holes I9 in Figures 1, 2, 3 and 5, has four radially proand 20 near the end of the bit. This construcieeting p r 23 and re tion permits the use of one solid unbroken ingrooves 25 are provided in the several portions 0 sert 28, or 3| across the face 01' the bit. This eliminates the weakness introduced by a center water hole and the two separate inserts against the bit. In drilling, great side pressure develops on the ends of the inserts. This pressure tries to narrow the bit and to reduce its guage. In those bits where two inserts are used on each cutting edge across the hit, some sort of washer or spacer must be used in the center to maintain the water outlet. The end pressure on the inserts frequently forces the two separate inserts together and closes the water hole. With the two tapered outlets I9 and 20, this weakness is avoided. The,

angle of the inlets is such that the inlets are not easily plugged by drill cuttings if the rock happens to be soft. The water is forced obliquely to thelface of the hole and, because of the rotation of the bit in drilling, a swirling action ismaintained bythe water. This thoroughly mixes v the water with the cuttings and reduces the dust hazard. Also 'it tin'gsl. I The outer ends of the inserts do more of .the work in drilling. The inclined water holes give the outer corners of the inserts the most effective cooling and thus prolong the drilling life of the inserts. The long drill body' with the stiffening afforded by the guide collar, also reduces the vibration of thedrill body and this in itself aids in keeping the drill cool.

".It is believed that the nature and advantages of my invention will be apparent fromtheforegoing description. Having thus described my lnvention, I claim: j

In combination, a drill rod having a bit receiving end composed of a length of the full diameter of the rod and a tapered portion extended from'the length of fulldiameter, said tapered portionbeing provided with screw threads, and aldrill bit having an elongated guide collar fitting closely on the portion of full diameter of the rod for a substantial distance above the screw helps to'remove the drill cutlow the threads and the rod having a reduced cylindrical extension in said socket and bearing on the bottom thereof, the drill rod having a central water passage and the drill bit having a central water passage in communication therewith, the passage in the drill bit being branched below the rod into smaller downwardly diverging passages, the drill bit having a transverse under cut groove across its working face and a hardened insert in said groove extending full width of the drill face, the diverging passages opening on the working face of the drill bit on opposite sides of said insert.

;. 1 WILLIAM R. WADE.

REFERENCES CITED The following references are of record in the file of. this patent:

V UNITED STATES PATENTS Number Germany Nov. 24, 1938 

